Given the unprecedented valuations of some tech companies and the low-volatility regime, which until recently dominated global financial markets, concerns about financial bubbles and crashes have intensified. Bubbles and their subsequent busts are predominately considered to be negative phenomena: they are often described as financially wasteful, economically inefficient, and socially destructive. Indeed, almost $6 trillion evaporated after the dotcom-collapse in the early 2000s, and the global economic system crashed when the financial bubble burst in 2008.